The present invention relates to mounting devices, and more particularly to a bracket for mounting the components of a breakerless ignition system to the leg portion of an armature core.
The conventional ignition system which has been employed with internal combustion engines for many years comprises a primary and a secondary winding that are inductively coupled with one another, a spark plug connected across the terminals of the secondary winding, and switching means for closing a circuit that enables current flow in the primary winding and for opening that circuit at a time in the engine cycle when the spark plug is to be fired. The switching means which has been employed with such ignition systems for many years comprises a pair of hard metal breaker points that are actuated by means of a cam mechanism rotated in timed relation to the engine cycle, and a condenser connected across the points to minimize arcing between them. More recently, however, solic state switching devices are being utilized to replace the conventional condensor and breaker points in ignition systems due to their efficient operation and long service life.
One breakerless ignition system that is particularly advantageous in its application to a magneto ignition system for small engines of the type used for powering lawn mowers, small pumps and electrical generators is shown in Tharman, U.S. Pat. No. 4,270,590 which is assigned to the assignee of the present invention. The breakerless ignition system shown therein has a switching device that includes a transistor for controlling flow of current through the primary winding of an induction coil, and a trigger coil which cooperates with a rotating magnet and with the armature core to provide a source of biasing current for the transistor whereby the transistor is switched on and off in timed relation to the engine cycle at all engine speeds.
It is desirable to mount the transistor and trigger coil of such a breakerless ignition system within the existing spaced limitations of small engines so that redesigning of the engine components is unnecessary. It is also desirable to mount the trigger coil so that it is properly positioned with respect to the rotating magneto magnet, and in such a manner that the wires connecting the transistor, trigger coil and induction coil do not break from vibrational stresses. One such mounting arrangement is shown in the aforementioned Tharman patent and includes an L-shaped bracket fastened in place by means of a screw to a leg portion of the armature core.